The invention relates to a power management scheme, and more particularly to a power management apparatus used in a system comprising multiple batteries and corresponding power management method.
Generally speaking, for a system comprising a single battery, a conventional gauge circuit is provided and used with the single battery for measuring state of charge and/or remaining capacity of this single battery. However, in a system comprising multiple batteries, the conventional gauge circuit cannot separately measure state of charge and/or remaining capacity of each battery. Actually, the gauge circuit can be only used to measure the state and/or capacity of a primary battery (i.e. a main battery), and the states and/or capacities of other batteries are to be estimated by using another look-up table scheme. Unfortunately, the look-up table scheme cannot accurately estimate the states or capacities of other batteries. The error rate made by the estimation of the look-up table scheme usually falls within a range from thirty percent to fifty percent, and it becomes not acceptable for the system to execute more accurate operations based on the estimation result. Accordingly, it is important to provide a novel scheme for separately and more accurately measuring states and/or capacities of multiple batteries for the system.